In the weaving of fibrous yarn, fluff is produced by the unwinding. This fluff becomes detached and is deposited on the weft yarn, thus causing the following problems:
when the weft is inserted by mechanical means: the fluff which is not removed is the cause of defects in the woven material; PA1 when the weft is inserted pneumatically: the presence of fluff is the cause of difficulties, and it may even not be possible to transfer the weft. PA1 when the first distributor is controlled mechanically, compressed air arrives not only in the utilization circuit through the main line and the second distributor which is initially open, but also fills the chamber passing through the restriction of the branch line. PA1 After a period of time which can be modified by the adjustable restriction, the supply pressure of the second distributor is reached; the state of the latter is changed, which cuts the supply to the utilization circuit. PA1 When the first distributor is no longer controlled and recloses, the chamber empties rapidly through the non-return valve and the second distributor also returns to its initial state, allowing the beginning of a new identical sequence next time the first distributor is controlled.
For cleaning to eliminates the fluff, installations exist for blowing air which operate permanently and are common to a set of looms, with a sliding carriage. These installations are troublesome and difficult for the operator; the frequency at which they pass each point or area to be cleaned remains inadequate and their power consumption is high.